The present invention relates to a combination of pipes and a gasket installed between the pipes for connecting the same. In particular, manifold pipes of an automobile are securely sealed by the gasket.
Conventionally, when pipes are connected together, flanges are attached to the end portions of the pipes, and the flanges are connected or tightened together with a gasket therebetween. However, since the flanges have to be formed on the pipes, it takes an additional labor and cost. Therefore, the formation of the flanges is not practical.
In case the pipes are male and female pipes engaging with each other, a gasket formed of heat resisting resin or heat resisting rubber may be disposed between the male and female pipes. However, although it is simple in connecting the pipes, since the manifold pipe is heated in use to very high temperature, the gasket made of the heat resisting resin or rubber may not sufficiently seal between the pipes.
In Japanese Patent Publication (KOKAI) No. 49-51443 corresponding to U.S. patent application Ser. No. 269,936 filed on Jul. 10, 1972, an annular gasket is used to connect plastic tubes. The annular gasket is made of a thermoplastic resin, and includes inner and outer portions connected by a base portion. Since the gasket is disposed between two plastic pipes with different diameters or inclined surfaces, the gasket may not be fixed or positioned to the pipes. Also, since the gasket is made of a thermoplastic resin, the gasket is not suitable to the manifold gasket.
In Japanese Patent Publication (KOKAI) No. 10-48381, a metal seal 22 formed of a main portion 22a and a flange 22b is disposed between two members 70, 80 with a ring 33. The metal seal 22 provides resiliency, but it does not directly seal between two members.
In view of the foregoing, the present invention has been made, and an object of the invention is to provide a combination of pipes and a metal gasket for connecting the pipes exposed to high temperature easily and securely.
Another object of the invention is to provide a combination as stated above, wherein the gasket can be easily positioned relative to the pipes.
A further object of the invention is to provide a combination as stated above, wherein a proper sealing pressure can be applied to the gasket to securely seal between the pipes.
Further objects and advantages of the invention will be apparent from the following description of the invention.